CHAPTER ONE
1. INTRODUCTION
1.1 Backgroundof study
Worldwide petroleum-based energy
resources are being depleted – onshore crude oil production peaked
decades ago but our demands for petroleum are still going up (McCarthy, et al.2011).
The United States’ continued dependency on imported petroleum,
particularly from the Middle East, has become an important national
security issue (John, et al.1998). Competition for global
energy supply from emerging economic powers such as China and India has
added to the urgency for searching and developing alternative energy
sources that help us reduce our dependency on imported oil. Lastly,
environmental concerns such as pollution and global climate changes
provide further motivation to address the energy challenge that we face
today (Fazal,et al.2011).
Biofuels, which are fuels derived from
biomass such as vegetable oil, corn, soybeans, sunflowers, algae, wood
chips, etc., are ideally suited for meeting the future energy challenges
because they do not add to global climate changes. This is attributed
to the fact that plants use CO2 to grow during the photosynthesis
process; consequently, the CO2 formed during combustion of biofuels is
balanced by that absorbed during the annual growth of plants used as the
biomass feedstock (Karavalakisand Bakeas 2010). Another key
advantage of biofuels over other alternative energy sources is that they
can be burned (either alone or mixed with petroleum-derived gasoline)
in existing internal combustion engines (Knothe, 2010). Moreover, we can
utilize current infrastructure such as pipelines, delivery trucks, and
fueling stations to transport and distribute biofuels.
This report focused on the production of
biodiesel (which is an important biofuel) from vegetable oils. With the
conventional technology, vegetable oil mixed with alcohol (e.g.,
ethanol) reacts in large-scale batch reactors and in the presence of an
alkaline liquid catalyst (e.g., NaOH or KOH) to form methyl esters or
biodiesel and glycerol or glycerine. The transesterification reaction
can take up to 12 hours or longer to complete; and at the end of the
reaction, it is necessary to use an acid to neutralize the liquid
catalyst and to separate biodiesel and glycerol from the product
mixture. Apart from the increased costs in their separation and recovery
after the transesterification reaction, the alkaline catalysts are
corrosive to the equipment and will readily react with free fatty acids
to form soaps, an undesired byproduct. It is therefore of interest to
explore alternative approaches to the production of biodiesel from
vegetable oils, which can raise production efficiency and lower
production costs (William, 2010).
1.2 Scope of the study
This study evaluates the effect of
combustible flames of biodiesel on growth and haematological properties
of rats exposed to it over a period of ten days. This study will as well
be used as a reference material for further investigation into the
toxic effect of vegetable-oil-biodiesel on all living things, as well as
evaluation of other areas of toxicity.
1.3 Aimof the study
The aim of this study is to clarify whether the smoke generated from biodiesel will have any toxic effectan albino-rat.
1.4Objective of the study
The objective of this investigation is
to study the effect of vegetable oil biodiesel on the tissues of an
albino-rat (Rattus novergicus) such as blood, serum, heart, lung and
liver; with emphasis on the following areas of interest such as:
- The extraction of biodiesel as an alternative to the use of conventional diesel in automobile engine operation.
- Analyzing the extracted biodiesel and fuel diesel used in making the blends.
- To determine the toxicological effect of smoke from various blends
of biodieselon growth and haematological properties of rats exposed to
it over a period of ten days.
1.5Relevance of study
This study serves as a platform for
determining the quality of different diesel grades based on their
toxicity level and risk to health, so as to secure environmental
benefits and promote sustainable development.